Re: [PATCH v2] drm/qxl: fix qxl can't use in arm64

[Christian König <christian.koenig@xxxxxxx>]

Am 24.03.22 um 11:49 schrieb Cong Liu:
> qxl use ioremap to map ram_header and rom, in the arm64 implementation,
> the device is mapped as DEVICE_nGnRE, it can not support unaligned
> access. and qxl is a virtual device, it can be treated more like RAM
> than actual MMIO registers. use ioremap_wc() replace it.
>
> Signed-off-by: Cong Liu <liucong2@xxxxxxxxxx>

Looks sane to me, but I'm really not involved enough to fully judge.

Acked-by: Christian König <christian.koenig@xxxxxxx>

> ---
>   drivers/gpu/drm/qxl/qxl_kms.c | 4 ++--
>   drivers/gpu/drm/qxl/qxl_ttm.c | 4 ++--
>   2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/qxl/qxl_kms.c b/drivers/gpu/drm/qxl/qxl_kms.c
> index 4dc5ad13f12c..a054e4a00fe8 100644
> --- a/drivers/gpu/drm/qxl/qxl_kms.c
> +++ b/drivers/gpu/drm/qxl/qxl_kms.c
> @@ -165,7 +165,7 @@ int qxl_device_init(struct qxl_device *qdev,
>   		 (int)qdev->surfaceram_size / 1024,
>   		 (sb == 4) ? "64bit" : "32bit");
>   
> -	qdev->rom = ioremap(qdev->rom_base, qdev->rom_size);
> +	qdev->rom = ioremap_wc(qdev->rom_base, qdev->rom_size);
>   	if (!qdev->rom) {
>   		pr_err("Unable to ioremap ROM\n");
>   		r = -ENOMEM;
> @@ -183,7 +183,7 @@ int qxl_device_init(struct qxl_device *qdev,
>   		goto rom_unmap;
>   	}
>   
> -	qdev->ram_header = ioremap(qdev->vram_base +
> +	qdev->ram_header = ioremap_wc(qdev->vram_base +
>   				   qdev->rom->ram_header_offset,
>   				   sizeof(*qdev->ram_header));
>   	if (!qdev->ram_header) {
> diff --git a/drivers/gpu/drm/qxl/qxl_ttm.c b/drivers/gpu/drm/qxl/qxl_ttm.c
> index b2e33d5ba5d0..95df5750f47f 100644
> --- a/drivers/gpu/drm/qxl/qxl_ttm.c
> +++ b/drivers/gpu/drm/qxl/qxl_ttm.c
> @@ -82,13 +82,13 @@ int qxl_ttm_io_mem_reserve(struct ttm_device *bdev,
>   	case TTM_PL_VRAM:
>   		mem->bus.is_iomem = true;
>   		mem->bus.offset = (mem->start << PAGE_SHIFT) + qdev->vram_base;
> -		mem->bus.caching = ttm_cached;
> +		mem->bus.caching = ttm_write_combined;
>   		break;
>   	case TTM_PL_PRIV:
>   		mem->bus.is_iomem = true;
>   		mem->bus.offset = (mem->start << PAGE_SHIFT) +
>   			qdev->surfaceram_base;
> -		mem->bus.caching = ttm_cached;
> +		mem->bus.caching = ttm_write_combined;
>   		break;
>   	default:
>   		return -EINVAL;